Disinfection solutions for use in conjunction with contact lenses have been in use essentially as long as contact lenses have been available to the public. There is a large diversity in the makeup of the various known solutions, primarily due to the fact that to date no single solution has been found to meet all of the parameters desired in a single solution. For example, currently commercially available solutions such as ReNu Disinfectant (Bausch & Lomb), Optisoft (Alcon), and Optifree (Alcon) which offer low irritancy and/or hypersensitivity require a minimum of four (4) hours soaking to disinfect. Solutions such as Flexcare contain thimerosol which has been particularly problematical as a disinfecting or preservative agent. Because of these problems there has been an attempt to avoid thimerosol as an antimicrobial agent.
A second, and not small consideration, is contact lens material/solution compatability. Heat disinfection is not a practical alternative for use with high water content soft contact lenses. Some lenses entrap or react with various components of the disinfection solution making it impossible to utilize such solutions with those lenses. For this reason, proper patient compliance with lens/solution match-up directions is essential to maintaining contact lenses properly. Yet experience has shown that patient compliance with lens and solution manufacturer directions is not adhered to by a significant, although small patient population. Hence, there has been an effort to develop a disinfection solution which is generally useful for most, if not all contact lenses currently available.
Finally, not all disinfectant solutions are suitably effective against the entire range of microbial organisms which are of concern in the contact lens field. One such organism where disinfectants and preservatives have had limited success is Acanthamoeba. The present invention solution is effective against the cyst as well as the trophozite stage of these protozoa.